The keys of Mozart horns are discussed in remarkably thought-provoking detail. Apparently C alto is not the absolute highest horn key. A strong case is made here for the existence of D and Eb altissimo horns.

The part I find most surprising is that the difference in tone quality between horns and trumpets/trombones is nearly negligible when you get to D altissimo, but still very distinct at C alto. I am curious as to why the timbres of the two suddenly diverge at this point. There must be some kind of threshold that is crossed when you go from C up to D, but I don't know what it is.

Are any of you familiar with this? Better yet, does anyone know where I could hear recordings of all four instruments? If the author is so certain that D horns and D trumpets sound so similar, than comparison tests must have been conducted in modern times - implying that there are in fact a very few D altissimo horns out there today.

Interesting that you posted this.... I have been lately listening to ALOT of Mozart and really studying the differences between written music for horn/trumpet/etc etc etc.

I played Jazz trumpet for many years in local bands while I played Horn in college and community orchestras. Some of what you are discussing MIGHT be the differences in instrument quality....something that has VERY much become a personal concern for me.

I have a trumpet that is nearly 100 years old. It is silver, and has such a warm and beautiful tone. Not at all like modern trumpets which are rather brassy. My antique trumpet plays more like a Horn. It was an issue back when I played regularly because you could hear my trumpet out of the others.
I even played Horn lines after a bit of transposition.
Sadly, I have a new French Horn (double) that I bought after 20 years away from music...this is not a nice horn....sounds cheap and brassy and I am saving for a replacement. But for now, it is all I have.

So, I'm not exactly sure what you are asking/posting....are you speculating about the tone of the other brass instruments at a similar range? Like C alto?


I think that Mozart more than most composers really understand the unique quality of the Horn and how, at any range, it has such a warm and deep tone.